Collapsible trestle.



J. R. ANDERSON.

COLLAPSIBLE TRESTLE.

APPLICATION FILED SEPT. 5, 1912.

1,147,668. Patented July 20, 1915.

mrsn snares e JOHN R. ANDERSON, 0F lyroLrnn, ILLINoI's, AssrGnoR orONE-HALF 'lO JOHN HERS'IEDT, or MOLINE, ILLINOIS. a

COLLAPSiBLE Tamera.

Application filed September 5, 1912. Serial No. 718,630.

To all whom it may concern: I

Be it known that I, JOHN R. ANDERSON, a citizen of the United States,residing at Moline, in the county of Rock Island and State of Illinois,have invented certain new and useful Improvements in CollapsibleTrestles, of which the following is a specification.

My invention relates in general to collapsible trestles, and moreparticularlyto trestles adapted to be used in connection with theerection of buildings and various engineering constructions.

One of the principal objects of the invention is to enable theconstruction of a trestle wherein the principal elements are or may beof commercial materials readily obtainable, the construction requiringnecessarlly only one specially prepared part and this being of simpleform.

A further object of the invention is to provide a trestle of'thecharacter descrlbed which may be readily adjusted to suit variousconditions, so constructing and arranging the parts that littletime willbe lost in changing them from one ad usted relationship to another.

'A still further object of the invention is to provide a collapsibletrestle wherein the parts will of their form give a maximum supportingstrength to the trestle, permitting thereby the use of longer supportswithout danger of collapse of the device than is possible where a lessefficlent arrangement 1s present.

An additional object of the invention 1s to provide a device of thissort which will readily accommodate itself to any of the usualinequalities and unevenness of the ground, floor or other surface uponwhich the trestle rests.

Further objects and advantages of the invention will be apparent as itis better understood from the following description which, taken inconnection with the accom-' panying drawing, illustrates one preferredembodiment thereof.

On the drawing :-Figure 1 is a perspec- Specification of Letters Patent.

PatentedJuly 20; 1 9 5.

view disclosing the means of fastening the i legs or supports ofthetrestle to the clamp- 1ng members, and Fig. i is a sectional view of oneof said clamping members. I

For the purpose of lllustratlng my invent1on I have shown the sameembodied in a trestle composed primarily of an I-beam 10,

a pair of clamps 11 and, supports 12, a pair of which is secured in eachclamp, it being understood, however, that although an I- beam isemployed in the present instance; to provide the main horizontal member,various other forms of commercial structural metal may be utilizedefficiently, it only being necessary that the clamps be adapted toconnect the supports 12with the particular form of horizontal memberemployed.

Each of the clamps v11 is preferably formed of an elongated slotted body13 adapted to receive within the slot or groove 14 the lower horizontalflanges-15 of the,

angle iron 10. Above each side of the groove 14 and spaced inwardlythereof isprefer ably provided an upwardly extending wall or lip 16adapted to. rest against the web 17 of the I-beam to strengthen andstiffen the structure. At an end of the clamp, preferably the outer end,are formed two downwardly depending and diverging supportreceivingsockets 18 into which the supports 12 are adapted to be secured. Thesesockets may be disposed in a vertical plane, but I prefer to slightlyincline them to the vertical, as shown in Fig. 4:, so that when thevarious parts are assembled the supports 12 'at both ends will beinclined inwardly of the trestle an equal amount. Disposed through thebottom of each clamp and communieating with the groove 14: I haveprovided an aperture 19 threaded internally and adapted to receive a setscrew 20, said aperture 19 being preferably inclinedto the vertical andtoward the sockets 18 to permit the end of theset screw engaging'thelowermost surface of the end of the I-beam to exert its greatestretaining force toward the end of the trestle in the direction of theinclined plane in which the legs or supports are disposed.

In Fig. 3 one method of fastening the supports 12 within the sockets 18is villustrated, ordinary gas or other metallicpipesv being utilized toprovide the supports for the trestle'inthe present instance, the ends ofthese pipes being secured in the sockets in threaded engagementtherewith as at 21,

it being manifest, however, that other forms of commercial buildingmaterial may be employed for this purpose and may be fitted within thesockets 18 in any preferred manner without departing from the spirit andscope of the invention, or sacrificing any of its advantages.

It is apparent that a trestle made in pursuance of my invention ispossessed of a large degree of flexibility, permitting it readily toadapt itself to various uneven surfaces. lhe I-beam or other structuralmetal used to provide the main horizontal member ordinarily possesses acertain degree of elasticity which cooperating with the movementpermitted by the sliding fit of the L beam with the clamps carrying thesupports enables the structure to accommodate itself readily to thevarious irregularities of the surfaces upon which structures of thiskind usually rest when in use, or readily obtainable in commercialforms.

It will be apparent that the trestle hereinbefore described may beconstructed by merely providing suitable clamps, the other members allusually being present among the waste incidental to large engineeringand building operations during their preliminary stages.

It will be manifest also that the parts may be assembled and removed orreadily adjusted with little effort on the part of the operator as onlya single set screw is employed in each clamp.

It is obvious also that various changes may be made in the form andarrangement of the parts without departin from the spirit or scope ofthe invention, or sacrificing any of its advantages, the formhereinbefore disclosed being merely one preferred embodiment thereof.

1 claim 1. In a collapsible trestle, the combination of a structuralmember, provided with lateral flanges at its bottom edge a pair ofmetallic legs, and a clamp having a pair of diverging sockets disposedin a plane inclined to the vertical and in which said legs are engaged,said clamp being slidably connected with the flanges of the structuralmember to move freely longitudinally thereof when the trestle isunloaded and adapted to automatically grip said flanges when a weight issupported by said trestle.

2. In a collapsible trestle, the combination of an imperforatehorizontally disposed I- beam, two pairs of legs, and a pair of clampseach having a pair of diverging sockets disposed in a plane inclined tothe vertical in which a pair of said legs are engaged, each of saidclamps being interlockingly engaged in the lower flanges of said I-beamto slide freely longitudinally thereof when the trestle is unloaded andto automatically grip said flanges when a weight is supported on thetrestle.

3. A collapsible trestle comprising an I- beam, a pair of brackets, eachbracket having in its top an inverted T-shaped channel receiving thebottom flange and part of the Web of the li-beam, said bracket alsobeing provided upon its under side with a pair of depending socketsdiverging transversely of the bracket, there being an open-endedthreaded opening extending through the bracket adjacent one end of thebracket, a set screw in the opening, and tubular leg standards engagingthe respective sockets.

4. A bracket of the character described consisting of a single castingincluding a body having an inverted substantially T shaped channel inits top and depending sockets diverging transversely of the body, therebeing a threaded opening near one end of the body and piercing the bodyfrom top to bottom thereof in alinement with the channel, substantiallyas and for the purpose described.

5. A bracket of the character described consisting of a single castingincluding a body having an inverted substantially T- shaped channel inits top and depending sockets arranged at one end of the underside ofthe body and inclined at an obtuse angle to the longitudinal axis of thebody, there being a threaded opening piercing the body adjacent thesocket provided end of the body and inclined to bring its upper endsubstantially between said sockets, said opening communicating with thechannel.

JOHN R. ANDERSON.

Witnesses HENRY SCHMIDT, J OHN A. WAHLSTRAND.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Eatents, Washington, I). G.

